Phages also known as bacteria viruses, are recognized as the most abundant and diverse microbes. This diversity is adapting to the selective pressures such as the prevalence of the phage resistance mechanisms of bacteria. Phages invade and lyse bacterial through six steps (adsorption, injection, replication, transcription translation, assemble, release). Bacteria evolve to many anti-phage mechanisms to avoid phage infection and lysis. This paper focus on a variety of anti-phage mechanisms of bacteria.
Bacteria ; genetics ; virology ; Bacterial Physiological Phenomena ; Bacteriophages ; genetics ; physiology ; DNA Replication ; Evolution, Molecular ; Virus Attachment

Objective Pathogen and antimicrobial susceptibility in children with bacterial meningitis were reviewed.Methods The positive cultures of cerebrospinal fluid samples or blood samples and its antimicrobial susceptibility were analyzed in 401 patients with the clinical diagnosis of bacterial meningitis.Results 401 cases cerebrospinal fluid samples and blood samples submitted to microbiology laboratory, 97 cases (24%) were microscopically and culturally proven to be bacterial meningitis. The most frequent pathogen was staphylococcus aureus (28%), followed by the streptococcus pneumoniae (19%) and escherichia coli (13%). Pediococci as conditioned pathogen, were found in purulent meningitis patients. One of the isolates of Staphylococcus aureus was simultaneously resistant to both vancomycin and teicoplanin. Three isolates showed simultaneous resistance to imipenem/cilastatin.Conclusions Staphylococcus aureus as the predominant pathogens of pediatric ranks first among pediatric patients of purulent meningitis. Serious drug resistance of isolated pathogenic bacteria and its in antimicrobial susceptibility in the bacterial meningitis should be considered in clinical therapy.

Objective To discuss the value of echocardiography for the assessment of structure and function of right heart in normal Chinese adults Methods The structure and function of right heart was assessed by echocardiography according to 2010 guideline of American Society of Echocardiography (ASE). The echocardiographic data of right heart of 130 normal Chinese adults were analyzed to acquire the normal reference values of echocardiographic parameters and evaluate the differences of these results among different age groups. Results There were significant differences among different age groups for some of the parameters. Right atrium (RA) transverse diameter was greater in the middle-aged group than that in the young-aged group [(36.90±5.10) mm vs (33.90±5.20) mm, t=-2.79, P=0.006]. RA longitudinal diameter (RAL) and RA area (RAA) were smaller in the young-aged group than those in the middle-aged and old-aged groups [(40.10±5.10) mm vs (42.90±5.10) mm, (43.40±5.60) mm, t=-2.51 and-2.91, P=0.013 and 0.004;(11.90±3.20) mm2 vs (13.40±2.90) mm2, (13.90±3.60) mm2, t=-2.24 and-2.90, P=0.027 and 0.004]. Parasternal long-axis right ventricule outflow tract (PLAX RVOT), parasternal short-axis right ventricule outflow tract (PSAX RVOT) and pulmonary artery diameter (PAD) were smaller in the young-aged group than those in the middle-aged and old-aged groups [(24.20±3.00) mm vs (26.20±2.30) mm, (25.90±2.90) mm, t=-2.80 and-2.32, P=0.006 and 0.022;(24.70±3.00) mm vs (27.20±2.50) mm, (26.90±2.60) mm, t=-4.40 and -3.84, P=0.000 and 0.000; (20.60±2.00) mm vs (22.10±2.70) mm, (21.90±2.10) mm, t=-3.12 and-2.67, P=0.002 and 0.008]. RV lateral wall thickness was smaller in the young-aged group than that in the middle-aged and old-aged groups [(5.10±0.60) mm vs (5.60±0.60) mm, (5.40±0.70) mm, t=-3.12 and-2.22, P=0.02 and 0.028];DTI e wave was greater in the young-aged group than that in the middle-aged and old-aged groups [(14.90±3.70) cm/s vs (10.90±3.10) cm/s, (11.10±2.60) cm/s, t=5.82 and 5.49, P=0.000 and 0.000]. DTI a wave was smaller in the young-aged group than that in the middle-aged and old-aged groups [(12.50±3.90) cm/s vs (14.60±3.70) cm/s, (16.60±3.60) cm/s, t=-2.79 and -5.04, P=0.007 and 0.000] and DTI a wave was smaller in the middle-aged group than that in the old-aged group (t=-2.26, P=0.02). Tricuspid E wave was greater in the young-aged group than that in the middle-aged and old-aged groups [(0.61±0.11) m/s vs (0.51±0.11) m/s, (0.48±0.08) m/s, t=4.58 and 5.44, P=0.000 and 0.000]. E/A was greater in the young-aged group than that in the middle-aged and old-aged groups (1.45±0.30 vs 1.12±0.33, 1.10±0.27, t=4.58 and 5.44, P=0.000 and 0.000). No significant differences were found among different age groups in RV systolic function parameters, whereas a trend of decrease in RV diastolic function was detected. Conclusion Echocardiography can be useful in assessing the structure and function of right heart quantitatively.

Objective To explore whether dithiothreitol(DTT)is helpful for PreScission Protease to cut off the GST from GST?CT3 protein. Meth?ods The pGEX?6P?3/CT3 recombinant plasmid was transfected into Escherichia coli BL21,and the GST?CT3 fusion protein was purified by B?PER method. PreScission Protease was applied with 10 mmol/L DTT to cut off the GST,then the SDS?PAGE was performed for identification of the CT3 protein. Results Without DTT,it was very difficult for PreScission Protease to cut off the GST from GST?CT3 protein. However,in the pres?ence of 10 mmol/L DTT,PreScission Protease could cut off the GST easily as identified by SDS?PAGE. Conclusion 10 mmol/L DTT can help Pre?Scission Protease to cut GST from GST?CT3 protein,so as to achieve high concentration of CT3.

The Offsite Medical Accounting Information Supervising System was developed for patients of Sichuan new rural cooperative medical scheme (NRCMS) using the C#programming language under .NET development environ-ment based on Microsoft Visual Studio 2010 in order to solve the problems in offsite medical accounting information statistics and supervision for patients of NRCMS.The system is a B/S-based MVP 3-tier structure with VPN hard-ware firewall and VPN client software plus certificate built-in, and can thus be used to supervise the offsite medical accounting for patients of NRCMS, analyze their medical advice seeking indexes at other places, and provide data for the NRCMS fund management .

Objective To develop a multi-channel dry type biochemistry sensor with a compact structure and high measurement accuracy.Methods The principle of double beam compensation based on reference LED was applied to improve the measurement accuracy.The complex splitting system was replaced by MXN fiber bundle and free-form surface lens to make the instrument more compact and lightweight.Use of the adaptive amplification photoelectric detection improved the measurement accuracy while simplifying the process.Results and Conclusion It has been proved by experiments that this sensor has the advantages of high measurement accuracy, little interference and compact construction. This sensor may well meet the requirements of dry type biochemistry analysis.

Objective To evaluate the role of real-time three-dimensional transesophageal echocardiography(RT-3D TEE)in left atrial appendage (LAA)occlusion.Methods Consecutive 10 atrial fibrillation (AF)patients (CHADS2 ≥ 2 )with high risk bleeding underwent LAA occlusion under the guidance of TEE.The LAA orifice shape and characteristics of lobes were assessed,the size of LAA with RT-3D TEE wee measured before closer implanation,and the position of the LAA occlusion device were evaluated by RT-3D TEE.The correlational analysis between LAA diameter and occluder size was conducted.Results Among 10 patients,the test results revealed 8 cases with complete LAA occlusion and 1 case with incomplete occlusion,and 1 case with failed occlusion.Five cases showed approximate round LAA ostium,and the other 5 showed approximate oval ostium.The average number of LAA lobes were 2.2±0.7. LAA ostium long diameter were larger by 3D TEE compared with 2D TEE[(21 .8±5.1)mm vs (20.8±4.1) mm],and ostium short diameter were smaller by 3D TEE compared with 2D TEE [(16.1 ± 3.0 )mm vs (1 7.0±2.6)mm],however there were no significant differences between 2D and 3D TEE measurements,and the mean ostium diameter and LAA depth were comparable between two methods.LAA ostium long diameter,short diameter,average diameter and LAA depth assessed by 3D TEE and 2D TEE showed good correlation with occluder diameter (3D TEE:r =0.719,0.690,0.791 ,0.71 1 ,and P =0.029,0.040,0.01 1 , 0.032,respectively;2D TEE:r = 0.887,0.894,0.932,0.896,and P = 0.001 ,0.001 ,0.000,0.000, respectively).LAA occlusion device position assessed by RT-3D:6 cases with appropriate position, acceptable position with 2 cases,and 1 case with malposition.Conclusions RT-3D TEE can play important role in evaluating the morphology of LAA,accurately judging LAA ostium shape and size and position of the occlusion device.

Objective To evaluate right ventricular (RV)systolic function in type-2 diabetes mellitus (T2DM)patients.Methods Fifty T2DM patients and fifty normal controls were included in the study and underwent echocardiographic examinations.The following parameters were measured:1 ) Right heart dimensions,pulmonary artery (PA)diameter,pulmonary acceleration time (AT)and PA systolic pressure (PASP);2)RV systolic function:RV fractional area change (RVFAC),tissue Doppler-derived tricuspid lateral annular systolic velocity (S'),tricuspid annular plane systolic excursion (TAPSE),longitudinal strain of six RV segments by 2-dimensional speckle tracking imaging (2D-STI);3 )RV diastolic function:E,A ratio of the tricuspid inflow spectrum (E/A),E,E'(peak early diastolic velocity of the tricuspid annulus) ratio (E/E');4)RV Tei index.Results Statistic analysis showed that T2DM patients had thicker RV walls,wider PAs and shorter AT than the control group (P =0.000,0.001 and 0.000),while their right heart chamber sizes and PASP remained unchanged.Among systolic parameters,absolute values of RV longitudinal strain at the lateral wall-mid (lat-m),septum-mid (sep-m)and septum-basal (sep-b)segments were significantly lower in the diabetic group than the control group (P =0.001 ,0.000 and 0.005),whereas strain of the other three RV segments and RVFAC,TAPSE.S'were not significantly different.Moreover, E/A,E/E'and Tei index were all significantly different between the two groups (P = 0.000,0.000 and 0.006),indicating declined diastolic and general function of RV in the T2DM group.Conclusions RV myocardial strain by 2D-STI is more sensitive in detecting RV systolic dysfunction than TAPSE,S' and RVFAC.Among the six segments of RV walls,lat-m,sep-m and sep-b are better locations for 2D-STI than the other three.

Objective To study dynamic expression of Oct-4 during development of colorectal cancer (CRC) and investigate the association between Oct-4 expression and prognosis of patients with CRC.Methods CRC tissues, matched non-tumor tissues and colonic polyp tissues were collected and Oct-4 expressions were analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), flow cytometry analysis (FCM) and immunohistochemistry (IHC).Medical records of patients with CRC were reviewed.Clinicopathological analysis was performed to assess the association between Oct-4 expression and certain chnicopathological parameters.Kaplane-Meier survival curve was conducted to evaluate association between Oct-4 expression and survival time of patients with CRC.Results The results of qRT-PCR showed that the relative expressions of Oct-4 mRNA in matched non-tumor, colonic polyp and CRC tissues were (0.23 ±0.16) × 10-5, (1.19 ± 0.76) × 10-5 and (3.79 ± 1.94) × 10-5 respectively, with a significant difference (F =8.633, P =0.001).IHC analysis displayed that the positive expression ratios of Oct-4 in matched non-tumor tissues, colonic polyp tissues and CRC tissues were 4.43％, 12.68％ and 40.51％ respectively, and a significant difference was discovered among them (x2 =66.311, P ＜ 0.001).Oct-4 expre-ssion in CRC was significantly correlated with pathological stage (x2 =7.248, P =0.007), lymph node metastasis (x2 =4.888, P =0.027), distant metastasis (x2 =5.732, P=0.017) and TNM stage (x2 =4.174, P=0.041).Kaplan-Meier survival curve analysis demonstrated that Oct-4 positive cases had a shorter median survival time (37.0 months) compared with Oct-4 negative cases (76.0 months), with a significant difference (x2 =14.050, P =0.001).Conclusion The expression of Oct-4 is step-wise increased during development of CRC.The abnormal expression of Oct-4 may play certain roles in the development of CRC.Oct-4 may be an important biomarker for the clinical diagnosis, assessment of disease and prognosis in CRC.

Objective To establish a simple and rapid detection technique for Oncomelania infected with Schistosoma japonicum(SJ), with high sensitivity and good specificity .Methods The gene fragment of SJ was amplified by PCR , and cloned into the T-vector to construct positive-reference.An isothermal nucleic acid amplification reaction system for detecting Oncomelania infected with SJ was set up , and its sensitivity was analyzed by detecting positive-reference diluted according to geometric proportion , and its specificity by detecting the genomic DNA of relative samples .Then, a corresponding means of purifying nucleic acid was designed to assemble a reagent detecting Oncomelania infected with SJ . This reagent was validated by detecting Oncomelania samples.Results The 213 bp amplified products were obtained and used to construct recombination T-vector for positive reference .An isothermal nucleic acid amplification reaction system was set up for detecting Oncomelania infected with SJ , and the amplification results could be simply determined by color change, with better sensitivity and specificity .The reagents for detecting Oncomelania infected with SJ were assembled , which could detect samples containing only 1% infected Oncomelania.Conclusion A visible detection method for Oncomelania infected with SJ is successfully established and validated .